Abstract: Stabilized antimicrobial compositions containing an antimicrobial amount of 2,2-dibromo-3-nitrilopropionamide in water miscible organic solvents. The stabilizer used is selected from chain-breaking antioxidants of the phenolic or amine type in an amount in the range of 0.001% to 0.5% by weight of the composition. Typical examples of stabilizers are: 2,6-di-tert-butyl-p-cresol; 4,4'-bis-(2,6-di-tert-butylphenol); 2,6-di-tert-butyl-.alpha.-methoxy-p-cresol and N-phenyl-.beta.-naphthylamine. The antimicrobial compositions also contain one or more water miscible organic solvents selected from those known in the art, in which the 2,2-dibromo-3-nitrilopropionamide is at least partially soluble. The compositions according to the present invention are characterized by their outstanding stability, compared with formulations which do not contain these stabilizers.